The seventh season of the American television medical drama Grey's Anatomy, began airing on September 23, 2010 on the American Broadcasting Company (ABC), and concluded on May 19, 2011 ending the season with a total of 22 episodes. The season was produced by ABC Studios, in association with Shondaland Production Company and The Mark Gordon Company; the showrunner being Shonda Rhimes and head writer Krista Vernoff. The season follows the aftermath of the season 6 shooting, in which Derek Shepherd (Patrick Dempsey), Alex Karev (Justin Chambers) Reed, and Charles are shot, and a total of 11 people died. Cristina Yang (Sandra Oh) was the most affected by the shooting, quitting her job. Cristina and Owen later marry with "her person", the show's protagonist Meredith Grey (Ellen Pompeo), as her maid of honor. Meredith and Derek start an Alzheimer trial, with Meredith suspecting that Richard Webber's (James Pickens, Jr.) wife Adele (Loretta Devine) may have Alzheimer's. Arizona Robbins (Jessica Capshaw) leaves for Africa after getting a grant leaving Callie Torres (Sara Ramirez) despondent. She sleeps with Mark Sloan (Eric Dane) and becomes pregnant by chance. Arizona returns, confessing her love for Callie. Meredith messes up the trial for the sake of Adele only to have Alex find out and tell Hunt, leading to Meredith kicking him out of her house. Derek leaves Meredith with Zola. Lexie Grey (Chyler Leigh) decides to give Mark a second chance but later starts a relationship with Jackson Avery (Jesse Williams). Teddy Altman (Kim Raver) starts a relationship with Andrew Perkins (James Tupper), a trauma counselor, but later falls for her patient, Henry Burton. This season marks the first appearance of Caterina Scorsone as Derek's sister, Dr. Amelia Shepherd, who becomes a series regular in season 11. The season ended with an average of 11.41 million viewers and was ranked #31 in overall viewership and was #9 in the 18-49 key demographic. Loretta Devine won the Outstanding Guest Actress in a Drama at the 63rd Primetime Emmy Awards. The season also garnered 7 nominations at the 37th People's Choice Awards and also won the Outstanding Drama Series at the NAACP Image Awards. Episodes The number in the "No. in series" column refers to the episode's number within the overall series, whereas the number in the "No. in season" column refers to the episode's number within this particular season. "U.S. viewers in millions" refers to the number